1. Field of the Invention
The present invention provides 4-halo-5-(hydroxymethyl) imidazole compounds that are useful as intermediates of medicines such as hypotensive drugs and the like.
The 4-halo-5-(hydroxymethyl) imidazole compound can be converted upon oxidation with manganese dioxide or the like into a 4-halo-5-formylimidazole compound.
2. Description of Prior Art
The 4-halo-5-(hydroxymethyl) imidazole compound has heretofore been synthesized by reacting a 5-(hydroxymethyl) imidazole compound which is a starting material with a halogenating agent such as an N-chlorosuccinimide to halogenate the position 4 of an imidazole ring. For instance, Japanese Patent Publication No. 64428/1988 discloses a 4-chloro-5-(hydroxymethyl) imidazole compound synthesized by the above-mentioned method and having at the position 2 thereof an n-propyl group, an n-butyl group, a t-butyl group, a cyclopentyl group, an m-butoxyphenyl group a p-methylphenyl group, a p-methoxyphenyl group and a p-chlorophenyl group, and Japanese Laid-Open Patent Publication No. 23868/1988 discloses a 4-chloro-5-(hydroxymethyl) imidazole compound having an n-heptyl group and a methoxyethyl group at the position 2 thereof.
The 5-(hydroxymethyl) imidazole compound used as a starting material in the above-mentioned method is prepared by a method of reacting an iminoester compound with a dihydroxyacetone in the liquid ammonia or by a method of reducing a 5-formylimidazole compound with a sodium borohydride. According to the former method, the starting material is handled with difficulty, the reaction apparatus becomes complex, the yield is low and the cost of production is high. The latter method, on the other hand, uses the 5-formylimidazole compound which is an expensive starting material. In either case, therefore, synthesis of the 4-halo-5-(hydroxymethyl) imidazole compound by using the 5-(hydroxymethyl) imidazole compound as a starting material, is not practicable.